and tamerlan tsarnaev. suspect number two is still believed to be in that area. that is why you're seeing all that you're seeing. officials are saying they believe it's really important that they try to capture him alive. they are saying that they are going to do everything they can to do that. the reason for that is because there are a lot of questions that they would like to ask him, namely, if there is a third party involved, or more people involved, if there are other plots. if this is bigger than just the two men, and that is something that we've heard from officials and authorities before, this is the case in this particular incident we're being told. one official said -- one source said it's amazing how calculating these guys were. they were living within a half mile of where they placed these bombs. authorities are looking to see if these two men left the country at any time. we are guessing that they -- and authorities believe they came in with their family roughly in about 2002, 2003, so they've b